Rain, snow and other harsh weather elements can have a devastating effect on the structural integrity of exterior building materials. Specifically, permeation and infusion of moisture and air into many exterior building materials can often result in the rot or decomposition of same. Wooden building materials, and especially wooden doorframes or doorjambs, are particularly susceptible to moisture and/or air-induced rot due the inherent porosity and fibrous or cellulosic composition of wood in general.
Unfortunately, and in the exemplary context of wooden doorframes or doorjambs, application of expensive exterior paints and/or sealants thereto do not provide sufficient long-term rot-resistant capabilities, as the structural, molecular or polymeric integrity of such paints and/or sealants is often disrupted or broken down by the infusion therein of moisture, air, dirt, dust and other foreign particulates. As such, paints or sealants applied to exterior wooden doorframes or doorjambs eventually peel from the surfaces thereof, and/or deteriorate in areas of greater molecular or polymeric breakdown; thus, exposing the wooden material therebeneath to the destructive forces of moisture, air and foreign particulates. Additionally, application of multiple layers of such paints and/or sealants often only exacerbates the problem, typically causing premature peeling due to the weak molecular bond between the layers, a structural deficiency most aptly attributed to an application process requiring the drying of individual paint/sealant layers prior to application of subsequent layers.
An alternative to the application of paints and/or sealants to wooden doorframes or doorjambs is to securely affix a plurality or an assembly of weathering plates to the exterior surfaces thereof. Such weathering plates are typically formed from plastic, cut or molded to shape, and affixed to the wooden doorframe or doorjamb via nails or wood screws. Unfortunately, because a multitude of such plates are typically assembled over the wooden structures, a plurality of gaps or spaces form between each adjacent or abutting plate, thereby providing several openings for the passage of moisture, air, and/or foreign particulates therethrough; thus, resulting in eventual rotting of the underlying wooden doorframe or doorjamb. Additionally, fastening such plates to the wooden structures via nails or screws create further openings or apertures for the introduction of air, moisture, and the like, therein and therethrough. Examples of such products may be seen with reference to U.S. Pat. No. 5,901,510 to Ellingson.
In an attempt to overcome the disadvantages associated with the application of paints, sealants, or weathering plates over wooden doorframes, doorjambs, or the like, many construction materials manufactures often apply or extrude thermoplastic melts and/or other hot melts over the wooden doorframe or doorjamb to provide a more permanent and structurally rot-resistant barrier thereover. However, the materials and equipment requirements of such extrusion processes render the application of such extrusion processes highly expensive, inefficient and, as such, impractical. Specifically, many thermoplastic melts are often extruded onto an adhesive-covered wooden doorframe, doorjamb, or core, and thereafter, permitted to cool. If the application process and curing of melt and adhesive is successful, the adhesive effectively forms a bond between the cooled melt and the wooden core. However, if the application process and curing of the melt and adhesive is unsuccessful, the cooled melt will often prematurely break free or peel away from the wooden core, exposing same to rot-inducing air and moisture elements, and resulting in excess materials waste in the long term. Additionally, even if successfully cooled and cured, such melt-adhesive based extrusions are not immune to fluctuations in extreme temperature, and, as such, may still peel or break free from the wooden core as a result of structural degradation of, or bonding failure between, the adhesive and melt. Furthermore, the extrusion dies and related equipment required to control flow, dimensions, and uniform application and thickness of thermoplastic melt over the wooden core, are often overly expensive, and, therefore, significantly contribute to the overall impracticality and high cost of such an extrusion process. Unfortunately, without such extrusion dies and machines, melts applied too thinly or non-uniformly over a wooden core are subject to cracking, premature peeling, and overall structural failure. Examples of such extrusion processes and products may be seen with reference to U.S. Pat. No. 6,357,197 to Serino et al., and U.S. Pat. No. 5,687,518 to Endo et al.
Although non-wooden doorframes, doorjambs, window frames, and the like, completely manufactured from extruded plastics or other rot-resistant materials are available, such solid-form extrusions are extremely expensive to manufacture, requiring expensive thermoplastic melts or powders and associated extrusion dies and machinery to extrude same.
An alternative to extruding entire doorframes or doorjambs from thermoplastic melts, compositions, or the like, is to only extrude a lower, non-load-bearing portion of the doorframe or doorjamb from extruded thermoplastics, or the like (i.e., areas of the doorframe/jamb especially susceptible to rot). Unfortunately, application of such products require an overly invasive and laborious method of installation, often necessitating the entire removal or excise of a desired (lower) portion of the door frame, replacement of the removed portion with a suitable extruded and cooled thermoplastic portion, and the securing of same. Still other methods of installation utilizing similar products require the creation of finger-joint connections in the ends of the extruded product and wooden doorframe/jamb, thereby facilitating end-to-end connection of same. Examples of such products may be seen with reference to U.S. Pat. No. 6,446,410 to Hagel, U.S. Pat. No. 6,425,222 to Hagel, U.S. Pat. No. 6,357,197 to Serino et al., U.S. Pat. No. 6,122,882 to Hagel, U.S. Pat. No. 5,950,391 to Hagel, U.S. Pat. No. 5,873,209 to Hagel, and U.S. Pat. No. 5,661,943 to Hagel.
Additionally, apparently absent from the prior art are protective doorjamb applications with integrally formed end caps that protect or shield the base or end of a doorjamb from the deleterious effects of air and moisture. Instead, some manufacturing processes include the use of end pieces or caps that may be added to the ends of a doorjamb during the extrusion of thermoplastic melts thereover. A product yielded as a result of such a process is seemingly structurally flawed, as the end piece and extruded melt, even with the use of adhesives, may not bond or cure properly, or may be susceptible to extreme temperatures and weather conditions, thereby resulting in the cooled melt prematurely breaking free or peeling away from the end piece; thus, exposing the underlying wooden doorjamb to rot-inducing air and moisture elements. Examples of such products may be seen with reference to U.S. Pat. No. 6,357,197 to Serino et al., and U.S. Pat. No. 5,687,518 to Endo et al.
As such, it appears that the inherent air/moisture-tight benefits of integrally formed end caps or boot-like enclosures for application onto doorjambs are not disclosed or taught in the prior art, nor is the combination of such closed-end, boot-like enclosures or end caps with the ends or lower portions of doorjambs.
Therefore, it is readily apparent that there is a need for a doorjamb end cap and method of installation therefor, wherein application of the present invention to wooden doorjambs permits the enclosed or encased portion thereof to effectively resist or avoid the onset of rot therein, and wherein the present invention is effectuated without expensive extrusion processes and/or thermoplastic melt and adhesive applications.